Early detection of significant high blood pressure (HBP) is important, but it is imperative not to overdiagnose. The prevalence of high blood pressure (HBP) in school-aged children is reported to vary from 1.2 to 12.4%. The literature is very sparse to answer the long-term meaning of HBP in the child. This study proposes to follow 1111 of the original 1769 children seen 27 to 30 years ago on whom we had recorded supine blood pressures, height, weight, and performed physical examinations. In a preliminary review, 30% of 80 children with HBP had sustained hypertension 15 to 25 years later as recorded in their hospital charts, indicating this to be a high risk group. Follow-up basic evaluation will include several blood pressure determinations (seated and supine), an update of the family and past medical history, physical and ophthalmologic examination, height, weight, and an index of body build, electrocardiogram, urinalysis, and basic blood chemistries. Using different values for the upper limits of normal blood pressure and testing many variables, answers to the following questions will be sought: Can one identify in childhood the potential hypertensive adult? What does an isolated high blood pressure reading in a child mean as to the future likelihood of fixed hypertension in the adult? What is the significance of childhood borderline hypertension? Which factors have prognostic significance to identify the patient at risk to develop meaningful hypertension in adult life?